The Federal Trade Commission has demanded information from Microsoft and interviewed competitors as the agency’s antitrust investigation heats up. The probe follows ProPublica reporting on how the company skirted and potentially violated federal law.

The Federal Trade Commission is investigating Microsoft in a wide-ranging probe that will examine whether the company’s business practices have run afoul of antitrust laws, according to people familiar with the matter. In recent weeks, FTC attorneys have been conducting interviews and setting up meetings with Microsoft competitors.

One key area of interest is how the world’s largest software provider packages popular Office products together with cybersecurity and cloud computing services, said one of the people, who asked not to be named discussing a confidential matter.